JFB Content plugin without the comments part?

Absolutely! In the Social configuration area in the admin section, click on the Comments tab, and you can set exactly how the Comments will (or won't) show.

Should be very easy, but if you run into issues, just let us know!

The image that's shown can be specified through the Open Graph tags. To use these tags, simply enable the feature in the Open Graph tab in the Social configuration area of JFBConnect. Then, you can specify some defaults to use across your whole site for title, description, and image, by entering the following in the big box:
title=Default title
description=Your default description for your site
image=http://link.com/default.jpg

Then, on any page where you want to override these settings to specify better information for Facebook, you can put the following tags anywhere on the page:
{JFBCGraph title=Better title}
{JFBCGraph description=Better Description}
{JFBCGraph image=http://link.com/better.jpg}

Finally, there's an option in the Open Graph tab to automatically use the first image in an article as the default image for content pages.

Hope this helps, but if not, let us know!

Facebook only scans a page about ever 24-72 hours, so if you make Open Graph changes, the results won't happen immediately when a page is shared. That is likely part of the problem you're seeing with the images right now. You can use the Facebook linter, below, to see what Facebook will see on your page after you make changes, and this also updates Facebook's cache so that Likes from that page will use the updated info immediately:
developers.facebook.com/tools/lint

Now, as for the defaults, yes, if you set a default title and description, that will be used on all pages that don't have specific {JFBCGraph title/description} tags. Another thing to try is to leave the title/description defaults blank and don't use the on-page tags at all. Facebook will scan your page and 'guess' the best title and description, which usually is the standard meta title and description. However, it's free to choose it's own title/description, so that may not always be the case. With the 'use first image' setting, this may give you a good combination of title, description, and image for Facebook. Again, use the lint tool above to test out different combinations and see what happens.

Hope this helps, but if you need more help, just let us know!